What we learned in Friday practice at the F1 Canadian GP

Heavy rainfall punctuated Friday's Formula 1 free practice sessions at the Canadian Grand Prix, yielding a little over half an hour of dry running across the day.

Severe thunderstorm warnings accompanied the weather forecasts in Montreal and, although predicted high winds did not whip up a frenzy around the Circuit Gilles Villeneuve, a deluge of marble-sized hail interrupted the Friday pitlane displays ahead of FP1 prior to a period of heavy rain. The downpour let up shortly before the session, but a smattering of puddles around the Ile Notre-Dame track required attention before the session could properly get started.

With two rain-affected sessions, there was minimal information that could be gleaned from the stifled on-track action: a 20-minute hiatus in running at the start of FP1 sapped away at the session's run-time, while FP2 was also affected after the soft-tyre runs with an increase in precipitation that necessitated the return of the intermediate tyre.

The rest of the Montreal weekend looks set to be affected by rain, which is generally referred to by cliche-fanciers as "the great leveller". It'll do more than just water down the gravy in the paddock poutine stall, as it'll be up to the teams to consider how much they expect to compromise their set-ups depending on the weather forecasts.

However, there's always something to learn, even if Friday's sessions end up being wholly unrepresentative of the rest of the weekend. But it's likely that the rain is here to stay, judging by the local forecasts...

By the end of the opening practice session, the sun had burned through the smoke-grey clouds and helped to dry the circuit as it became suffused in a mysterious robe of steam. The drivers felt sufficiently confident to ditch the suite of wet-weather tyres and explore the circuit on softs, after which Lando Norris assumed the bragging rights with his time-topping effort at the end of the session - a 1m24.435s.

The hardy fans on Friday saw Norris top opening practice that started with no running due to huge puddles and ended with a dry track

Photo by: Andy Hone / Motorsport Images

Norris' effort followed a longer period of running in wet weather, which was paused shortly after it had belatedly begun. Zhou Guanyu aquaplaned at Turn 5 and caught the wall with his left-front tyre - causing suspension damage and the Sauber driver's stoppage at the following corner. The break in running allowed the circuit to bask in the sunshine which, when running resumed, quickly produced a dry line around the circuit.

Further threats of rain lingered into the afternoon, although the circuit was largely dry at the time FP2 had kicked off. This allowed the drivers enough time to log some soft-tyre laps before the conditions once again worsened as the radars became more colourful with mottled cells of inclemency.

This was a session dominated by Fernando Alonso's presence at the top of the order, as the Aston Martin seemed to build sufficient tyre temperature in low-grip conditions. He became the first into the 1m19s, and continued to improve upon his pace-setting efforts to ultimately land on a 1m15.810s - nearly half-a-second clear of George Russell's Mercedes.

"It's more important to figure out what actually happened and what implications that will have for this weekend or the rest of the year" Max Verstappen

Alonso had continued to circulate on the same soft tyres, as his race engineer Chris Cronin suggested that the team should save an extra set of the C5 tyre for an extra qualifying simulation in FP3, should conditions offer another window sans drizzle in Saturday's session. This allowed for his steady stream of improvements lap after lap, before the session changed gears at its midway point; in a dry session, the second half would usually be allocated to longer runs on the harder compounds, but instead the worsening weather necessitated exploration on the intermediate tyres.

Championship leader Max Verstappen suffered with power unit-based misfortune in FP2, aborting his lap to pit having smelt a smoky stench that was later diagnosed as an ERS failure, prompting Red Bull's finest to dig under the skin of his RB20 in an effort to identify the culprit.

"It's not ideal," the Dutchman rather understated. "I would have liked to drive more laps and some other people had a few more laps in the dry, a few more laps now in the wet. So, it's definitely not how I would have liked to get on in FP2. But I think it's more important to just figure out what actually happened and what kind of implications that will have for this weekend or the rest of the year."

It was a tough FP2 for Verstappen who completed just four laps before an ERS issue retrained him to the pits

Photo by: Sam Bloxham / Motorsport Images

Most forecasts have rain and thunderstorms scheduled over Montreal on Saturday, particularly in the afternoon; it's likely that the intermediate and wet tyres will continue to get a workout in FP3 and qualifying. Based on the order in FP2, this should hand the likes of Aston Martin and Mercedes a chance to shine at the front of the order, with Ferrari very much in the mix as well as Leclerc was matching Russell and Lance Stroll amid the changeable conditions.

McLaren also showed well in FP1's transition to dry weather, although this is as much about being on the circuit at the right time as it is about balance and downforce. Tyre warm-up in wet weather is a challenge, and requires drivers to be active at the wheel without inducing slides or other turning moments that produce one-way tickets into the barrier. Regardless, given McLaren's form at the moment, it led Oscar Piastri to suggest that the team has more to lose in wet conditions as it attempts to match its performance in the dry. That's also true of Red Bull.

Should qualifying become heavily dependent on the wet-weather compounds, it's likely that drivers will be able to stick with a single set of tyres through each phase and log multiple laps on a higher fuel load. Pirelli has spotted little overall wear during the wet conditions on the new track surface, as surface roughness seems to be forgiving and not providing too much abrasion. And this will persist into a dry crossover, according to its head of motorsport Mario Isola, as the traction-heavy nature of the circuit does not expose the tyres to too much lateral loading.

In the event that the circuit is ready for dry tyres, the new track surface might contribute towards sliding as it has yet to be properly rubbered in thanks to the changeable conditions. Pirelli did not achieve enough longer runs to assess if its predictions of graining were accurate, although there were a few reports that the tyres had started to grain in the opening phases of FP2.

Thundershowers are expected on Sunday afternoon, which may affect the race. In dry conditions, Pirelli anticipates it to be close-run between one and two stops, as was the case last year. And if it's fully dry in the grand prix, the choice between the two will come down to the strategic options from track position and assessing wear rates on the fly if further dry running on Saturday is limited.

If Aston Martin retains its strong tyre warm-up capabilities from FP2, Stroll could have a role to play in surprising at his home race. The Canadian's prowess in wet weather has often come as a result of his high-energy approach to steering wheel inputs, something that can cost a tenth or two in standard conditions as he sometimes fails to load his car in the right way. In the wet, however, this give him an edge in getting the wet-tyre tread blocks to move around and generate heat. The same is true of Yuki Tsunoda, as RB figured at the top end of the times in the second practice session. Their driving styles do put them more at risk if pockets of standing water begin to form, but generating the right tyre temperatures is half of the battle won.

Could Stroll star at home if conditions remain wet?

Photo by: Mark Sutton / Motorsport Images

But, as ever, it's always difficult to predict just how the order will stack up when rain falls. It's circumstantial at the best of times, and catching a circuit at peak dryness at the right time will ultimately decide the order if the forecast weather emerges.

"It's going to be a gamble always on which tyre to put on at which moment. Let's see if we get it right," reckoned chart-topper Alonso. "It was a tricky Friday for everyone. Not many laps in FP1, not many laps in FP2, no proper laps in dry conditions and no proper laps in wet conditions. We were in the middle of nowhere.

"We need to analyse a little bit the data and be very sharp. I think the right decision can gain you five seconds. The wrong decision, you are out of the race" Fernando Alonso

"But it could be like this in qualifying and the race, so it's still very useful information. We need to analyse a little bit the data and be very sharp. I think the right decision can gain you five seconds. The wrong decision, you are out of the race."

This is where the strategists on the pitwall earn their crust. Getting the drivers on the track at the right time is one thing - making sure they stay there to accept Lady Luck's bounty is quite another.

Following the pre-FP1 deluge, the marshals will be on high alert with the weather this weekend

Photo by: Sam Bagnall / Motorsport Images